Google Sites led the U.S. core search market in December with 65.7 percent of the searches conducted, followed by Yahoo! Sites (17.3 percent), and Microsoft Sites (10.7 percent). Ask Network captured 3.7 percent of the search market, followed by AOL LLC with 2.6 percent.

* Based on the five major search engines including partner searches and cross-channel searches. Searches for mapping, local directory, and user-generated video sites that are not on the core domain of the five search engines are not included in the core search numbers.

* Based on the five major search engines including partner searches and cross-channel searches. Searches for mapping, local directory, and user-generated video sites that are not on the core domain of the five search engines are not included in the core search numbers.

December 2009 U.S. Expanded Search Rankings

In the December analysis of the top properties where search activity is observed, Google Sites led the search market with more than 14.0 billion search queries, followed by Yahoo! Sites with 2.6 billion queries and Microsoft Sites with 1.6 billion searches. Bing experienced large growth during the month with a 6-percent increase in query volume to nearly 1.4 billion searches. eBay and Amazon Sites experienced gains in December as retail search activity picked up during the holiday season.

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